What is the Difference Between NFkb1 and NFkb2

The key difference between NFkb1 and NFkb2 is that the gene NFkb1 codes the protein NFkb1 in humans while the gene NFkb2 codes the protein NFkb2 in humans.

NFkb is a protein complex that controls the transcription of DNA, cytokine production, and cell survival. It is usually involved in cellular responses to stimuli such as stress, cytokines, free radicals, heavy metals, ultraviolet irradiation, oxidized LDL, bacterial or viral antigens. It also plays a key role in regulating immune responses properly against infection. Dysregulation of NFkb has been linked to cancer, inflammatory diseases, septic shock, viral infection, and improper immune development. There are five proteins in NFkb protein family: NFkb1, NFkb2, ReIA, ReIB, and c-ReI.

CONTENTS

1. Overview and Key Difference
2. What is NFkb1
3. What is NFkb2
4. Similarities – NFkb1 vs NFkb2
5. NFkb1 vs NFkb2 in Tabular Form
6. Summary – NFkb1 vs NFkb2

What is NFkb1?

NFkb1 is a protein in humans that is encoded by the NFkb1 gene. NFkb1 gene normally encodes a protein of 105 kDa (P105) in size. This protein can undergo cotranslational processing by the 26S proteasome to produce a 50 kDa protein (P50). The 105 kDa protein is a Rel protein-specific transcription inhibitor, while the 50 kDa protein is a DNA binding subunit of the NFkb protein complex. Moreover, the P50-RelA dimer is a transcriptional activator.

NFkb is a transcription factor that is activated by various stimuli like cytokines, free radicals, ultraviolet radiation, bacterial or viral products. The activated NFkb transcription factor can translocate into the nucleus and stimulate the expression of genes that are involved in a variety of biological functions. Under specific conditions, more than 200 genes can be targeted by NFkb in various cell types. The inappropriate activation of NFkb has been associated with inflammatory diseases. On the other hand, the inhibition of NFkb leads to inappropriate immune cell development or delayed cell growth. Furthermore, the NFkb1 protein has been shown to interact with several important proteins such as BCL3, C22orf25, HDAC1, IKK2, ITGB3BP, MEN1, RELA, RELB, STAT3, STAT6, etc.

What is NFkb2?

NFkb2 is a protein in humans that is encoded by the NFkb2 gene. This gene encodes a full-length protein that is 100 kDa (P100) in size. This protein is cotranslationally processed into an active protein which is 52 kDa (P52) in size. The proteins encoded by the NFkb2 gene can function as both a transcriptional activator and repressor depending on its dimerization partner.

P52-RELB dimer is a transcriptional activator, while P100 is a transcriptional repressor. Furthermore, the chromosomal rearrangements and translocation of this locus have been observed in some B cell lymphomas. This is due to the fusion protein formation after translocation. Moreover, there is a pseudogene for this NFkb2 gene on chromosome 18. The mutated version of NFkb2 protein causes adrenocorticotropic hormone deficiency and DAVID syndrome. DAVID syndrome is a pituitary hormone deficiency and CVID (common variable immune deficiency).

What are the Similarities Between NFkb1 and NFkb2?

• NFkb1 and NFkb2 are two proteins in the NFkb protein family.
• Both proteins belong to the class 1 NFkb protein complex.
• Both proteins can behave as a transcriptional activator and repressor.
• Dysregulation of both proteins can result in various diseases.
• They are made up of amino acids.

What is the Difference Between NFkb1 and NFkb2?

NFkb1 is a protein in humans encoded by the NFkb1 gene, while NFkb2 is a protein in humans encoded by the NFkb2 gene. Thus, this is the key difference between NFkb1 and NFkb2. Furthermore, NFkb1 protein full-length form of P105 cotranslates into active form P50. On the other hand, NFkb2 protein full-length form P100 cotranslates into active form P52.

The below infographic presents the differences between NFkb1 and NFkb2 in tabular form for side by side comparison.

Summary – NFkb1 vs NFkb2

NFkb protein complex is involved in controlling transcription of DNA, cytokine production, and cell survival. NFkb1 and NFkb2 proteins belong to the class 1 NFkb protein family. NFkb1 is a protein in humans encoded by the NFkb1 gene, while NFkb2 is a protein in humans encoded by the NFkb2 gene. So, this summarizes the difference between NFkb1 and NFkb2.

Reference:

1. “NFKB2 Nuclear Factor Kappa B Subunit 2 [Homo Sapiens (Human)].” National Center for Biotechnology Information, U.S. National Library of Medicine.
2. “NFKB1 Nuclear Factor Kappa B Subunit 1 [Homo Sapiens (Human)].” National Center for Biotechnology Information, U.S. National Library of Medicine.

Image Courtesy:

1. “Protein NFKB1 PDB 1bfs” By Emw – Own work (CC BY-SA 3.0) via Commons Wikimedia
2. “Protein NFKB2 PDB 1a3q” By Emw – Own work (CC BY-SA 3.0) via Commons Wikimedia